1. Field of the Invention
The present invention generally relates to a new and improved device for controlling the application of single or polyphase electrical power to electrical apparatus and, more specifically, to a new and improved modular vacuum interrupter or switch for controlling the application of three phase electrical power to a three phase motor.
2. Description of the Prior Art
Devices for switching single or polyphase, typically three phase, electrical power to low voltage electrical apparatus, for example, a three-phase motor, are old and well known in the prior art. Air magnetic switches as well as vacuum switches have been used for this purpose. These prior art switches are typically mechanically complex and are costly and time-consuming to assemble or disassemble. Hardware, such as nuts, bolts, screws, washers and similar fasteners, is typically used in abundance to assemble and maintain such switches as unitary structures. A need exists in the art for relatively inexpensive and simple single and polyphase vacuum interrupters or switches that may be easily and quickly assembled and disassembled without the need for the hardware typically used in the prior art devices. In order to reduce inventory requirements, a need also exists for modular components to enable the same vacuum switch module to be used in a single phase vacuum interrupter or in a polyphase vacuum interrupter.